Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Musculoskeletal System > Bone and Soft Tissue Infections > Flashcards

Bone and Soft Tissue Infections Flashcards

1
Q

What are the types of osteomyelitis?

A

Acute, subacute or chronic

Specific or non-specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

In what people is acute osteomyelitis most common?

A

Mostly children, boys > girls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the acute osteomyelitis associated with?

A 
History of minor trauma 
Diabetes
Rheumatoid arthritis 
Immune compromise 
Long-term steroid treatment 
Sickle cell disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the modes of spread of acute osteomyelitis?

A

Haematogenous spread in children and elderly
Local spread from contiguous site of infection e.g. trauma

Infants - infected umbilical cord
Children - boils, tonsillitis, skin abrasions
Adults - UTI, arterial line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the most common causative organism of acute osteomyelitis?

A

Infants < 1 - staph aureus, followed by group B strep, then E. coli

Older children - staph aureus, followed by streptococcus pyogenes then haemophilus influenzae

Adults - staph aureus, followed by coagulase negative staph, propionibacterium spp., strep pyogenes, mycobacterium tuberculosis etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is commonly the causative organism of acute osteomyelitis in butchers?

A

Brucella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is commonly the causative organism of acute osteomyelitis in fishermen and filleters?

A

Mycobacterium marium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In what patients is candida more commonly a causative organism of acute osteomyelitis?

A 
Debilitating illness 
HIV/AIDS
Long-term antibiotic treatment 
GI surgery 
Malignancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the special cases of acute osteomyelitis where causative organisms would be different from the normal population?

A

Diabetic foot and pressure sores - mixed infection, including anaerobes
Vertebral osteomyelitis - staph aureus, TB
Sickle cell disease - salmonella species
STD - gonococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the pathology of acute osteomyelitis?

A

Starts at metaphysis
Vascular stasis
Acute inflammation causing increased pressure
Suppuration
Release of pressure (medulla, sub-periosteal, into the joint)
Necrosis of bone (sequestrum)
New bone formation (involucrum)
Resolution or no resolution and development into chronic osteomyelitis
Septic arthritis in the bone can also develop, most commonly in the hip and elbow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is infected in acute osteomyelitis of long bones?

A

Metaphysis infected e.g. distal femur, proximal tibia, proximal humerus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the clinical features of acute osteomyelitis in infants?

A 
Signs can range from minimal to severe illness
Failure to thrive
Drowsy or irritability 
Can be minimal signs or very systemically unwell
Metaphyseal tenderness and swelling 
Reduced range of movement 
Positional change 
Commonest around the knee
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the clinical features of acute osteomyelitis in children?

A 
Severe pain
Reluctant to move - not weight bearing 
May be tender, fever and tachycardia
Malaise - fatigue, nausea and vomiting 
Toxaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the clinical features of acute osteomyelitis in adults?

A 
Primary OM seen in thoracolumbar spine
Backache
History of UTI or urological procedure
Elderly, diabetic or immunocompromised
Unremitting pain - keeping patient awake at night

Secondary OM much more common
Often after open fracture or surgery
Mixture of causative organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why do you need to be particularly aware of wounds that fail to heal and are likely to be infected that are close to the bone?

A

Because all of the necrotic tissue will need to be derided - both soft tissue and bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What investigations should be done if suspecting acute osteomyelitis?

A

FBC and WBC - neutrophil leucocytosis
ESR
CRP
Blood cultures 3x at peak temperature, 60% positive
U&Es - ill, dehydrated
X-ray - not useful in acute presentation, can take 1-2 weeks to show, shows metaphyseal destruction at later dtage
US - more useful in hip if infection is in the joint
Aspiration
Isotope bone scan - non-specific
Labelled white cell scan - non-specific

MRI is the best investigation - accurate and good for determining the extent of infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the differential diagnoses for acute osteomyelitis?

A

Acute septic arthritis
Trauma
Acute inflammatory arthritis
Transient synovitis

Rare - sickle cell disease, Gaucher’s disease, rheumatic fever, haemophilia

Soft tissue infection - cellulitis, erysipelas, necrotising fasciitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What would be seen on the radiographs of a patient with acute osteomyelitis?

A

X-ray will be normal in first 10-14 days
Later will show increasing metaphyseal destruction
Early radiographs will show minimal changes
Early periosteal changes happen 10-20 days
Medullary changes occur in lytic areas
Late osteonecrosis - sequestrum
Late periosteal new bone - involucrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What scans might be done for acute osteomyelitis?

A

Technetium-99m labelled bisphosphonate
Gallium 67 citrate delayed imaging
Indium-111 labelled WBC scan
MRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What microbiology is done for acute osteomyelitis?

A

Blood cultures in haematogenous osteomyelitis and septic arthritis
Bone biopsy
Tissue or swabs from up to 5 sites around implant at debridement in prosthetic infections
Sinus tract and superficial swab results may be misleading due to skin contaminant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the treatment of acute osteomyelitis?

A

Supportive for pain and dehydration
Rest
Splintage
Antibiotics - IV/oral switch 7-10 days, 4-6 week duration oral antibiotics depending on response and ESR
Empirical antibiotics while waiting for cultures - flucloxacillin and benzylpenicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does antibiotic choice depend on?

A

Spectrum of activity
Penetration to bone
Safety of long-term administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why might antibiotic failure occur?

A

Drug resistance e.g. beta-lactamases
Bacterial persistence e.g. dormant bacteria in dead bone
Poor host defences - diabetes, alcoholism
Poor drug absorption
Poor tissue perfusion
Drug inactivation by host flora
MRSA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the indications for surgery for acute osteomyelitis?

A

Aspiration of pus for diagnosis and culture
Abscess drainage - multiple drill holes, primary closure to avoid sinus
Debridement of dead/infected/contaminated tissue
Refractory to non-operative treatment > 24-48 hours - timing, drainage, lavage, infected joint replacements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the potential complications of acute osteomyelitis?

A 
Septicaemia
Death 
Metastatic infection 
Pathological fracture 
Septic arthritis 
Altered bone growth 
Chronic osteomyelitis
26
Q

When does subacute osteomyelitis occur?

A

Increased host resistance
Lowered bacterial virulence
Antibiotic usage

27
Q

What are the clinical features of subacute osteomyelitis?

A

Long history - weeks to months
Variable symptoms - pain, limp
Local swelling, occasionally warmth
Tenderness

28
Q

What are the differential diagnoses for subacute osteomyelitis?

A

Tumour e.g. Ewing’s sarcoma, osteoid osteoma

TB

29
Q

What are the features of Brodie’s abscess?

A

Subacute osteomyelitis
Older children
Painful limp, no systemic features
Radiographic lucency in long bone metaphysis

30
Q

What are the differential diagnoses for Brodie’s abscess?

A

Ewing’s sarcoma

31
Q

What are the investigations for subacute osteomyelitis?

A

X-ray
Bone scan
Biopsy - 50% positive
Grow organism

32
Q

What is the treatment of subacute osteomyelitis?

A

Curettage

Prolonged antibiotics

33
Q

When does chronic osteomyelitis occur?

A

May follow acute osteomyelitis
Much rarer in children
May start de-novo following an operation or open fracture, or in a patient with immunocompromise e.g. diabetes, elderly

34
Q

What are the features of chronic osteomyelitis?

A

Repeated breakdown of healed wounds
Often mixed infection
Usually the same causative organism at each flare-up
Cavities, possible sinuses
Dead bone - retained sequestra
Involucrum
Histological picture of chronic inflammation

35
Q

What are the most common causative organisms of chronic osteomyelitis?

A

Staph aureus still most common
E. coli
Strep pyogenes
Proteus

36
Q

What is the treatment of chronic osteomyelitis?

A 
Long-term antibiotics - local and/or systemic
Eradicate bone infection surgically 
Treat soft tissue problems 
Deformity correction
Massive reconstruction 
Amputation
37
Q

What are the potential complications of chronic osteomyelitis?

A

Chronically discharging sinus and flare-ups
Ongoing infection - metastatic, abscesses
Pathological fracture
Growth disturbance and deformities
SCC in 0.07%

38
Q

What is acute septic arthritis?

A

Infection in a joint

39
Q

What are the modes of infection that cause acute septic arthritis?

A

Direct invasion from penetrating wound, intra-articular injury or arthroscopy
Eruption of bone abscess
Haematogenous spread
Metaphyseal septic focus - either septic arthritis or osteomyelitis

40
Q

What are the most common causative organisms of acute septic arthritis?

A

Staphylococcus aureus most common
Strep pyogenes
Haemophilus influenzae
E. coli

41
Q

What is the pathology of acute septic arthritis?

A

Acute synovitis with purulent joint effusion
Articular cartilage attacked by bacterial toxin and cellular enzyme
Complete destruction of the articular cartilage

42
Q

What are the possible sequelae of acute septic arthritis?

A

Complete recovery
Partial loss of articular cartilage and subsequent OA
Fibrous or bony ankylosis

43
Q

What are the features of acute septic arthritis in neonates?

A

Picture of septicaemia
Irritability
Resistant to movement - more painful than acute osteomyelitis due to build-up of pressure
Systemically unwell

44
Q

What are the features of acute septic arthritis in children?

A

Acute pain in a single joint
Reluctant to move the joint in any way, consider bursitis where range of movement is normal
Increased temperature and pulse
Increased tenderness

45
Q

What are the features of acute septic arthritis in adults?

A

Often involves a superficial joint

Rare in healthy adults

46
Q

What are the investigations that should be done for acute septic arthritis?

A 
FBC
WBC
ESR
CRP 
Blood cultures
X-ray 
US 
Aspiration
47
Q

What is the most common cause of acute septic arthritis in adults?

A

Infected joint replacement

48
Q

What are the complication of acute septic arthritis in adults?

A

Death
Amputation
Removal of arthroplasty

49
Q

What is the most common causative organism of acute septic arthritis in adults?

A

Staph aureus

50
Q

What are the differential diagnoses for acute septic arthritis?

A 
Acute osteomyelitis
Trauma
Pseudogout
Irritable joint
Haemophilia
Rheumatic fever
Gout 
Gaucher's disease
51
Q

What is the treatment of acute septic arthritis?

A

General supportive
Antibiotics 3-4 weeks
Surgical drainage and lavage - arthroscopic lavage or open operation in infected joint replacements, followed by antibiotics

52
Q

What is tuberculosis of bones and joints due to?

A

Used to be due to TB, rickets and polio

Now due to trauma and degenerative joint disease

53
Q

What is the typical presentation of tuberculosis of bones and joints?

A

Bent children - unable to stand straight
Thoracic kyphosis
Lower limb deformities

54
Q

What are the classifications of tuberculosis of bones and joints?

A

Extra-articular - epiphyseal/bones with haemodynamic marrow
Intra-articular - large joints
Vertebral body - most common

Multiple lesions in 1/3rd

55
Q

What are the clinical features of tuberculosis of bones and joints?

A 
Insidious onset with general ill health 
Contact with TB 
Pain, especially at night
Swelling
Weight loss 
Low grade pyrexia 
Joint swelling 
Decreased range of movement (won't be seen in spine) 
Ankylosis 
Deformity
56
Q

What is the pathology of tuberculosis of bones and joints?

A

Primary complex in lung or gut
Haematogenous secondary spread to bones
Tuberculous granuloma
Role of nutrition and influence of other diseases e.g. HIV, AIDS

57
Q

What is the presentation of spinal tuberculosis?

A

Little pain

Abscess or kyphosis

58
Q

How is TB of bones and joints diagnosed?

A 
Long history 
Involvement of a single joint
Marked thickening of the synovium 
Marked muscle wasting
Periarticular osteoporosis
59
Q

What investigations should be done for TB of bones and joints?

A 
FBC
ESR
Mantoux tests
Sputum/urine culture
X-ray 
Joint aspiration and biopsy - AAFB identified in 10-20%, culture +ve in 50%
60
Q

What are the features of the x-ray of a patient with TB of bones/joints?

A

Soft tissue swelling
Peri-articular osteopaenia
Articular space narrowing

61
Q

What are the differential diagnoses for TB of bones and joints?

A

Transient synovitis
Monoarticular rheumatoid arthritis
Pyogenic arthritis
Haemorrhagic arthritis

62
Q

What is the treatment of TB of bones and joints?

A

Chemotherapy
Rifampicin, isoniazid, ethambutol and pyrazinamide - 8 weeks, followed by rifampicin and isoniazid for 6-12 months
Rest and splintage
Operative drainage rarely necessary

Musculoskeletal System (40 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions